This clinical immunology research program is based on three hypotheses: 1) Human auto-immune diseases (systemic lupus erythematosus (SLE), autoimmune thyroiditis) and neoplasia (chronic and acute lymphocytic leukemia (CLL, ALL), and the lymphomas) have direct counterparts in the mouse (autoimmune disease in lymphocytic choriomeningitis virus infected mice, and in NZB/NZW mice, and spontaneous and induced murine leukemias). 2) These diseases appear to be the result of a complex interaction between viral agents and host genes controlling viral infectivity, immune responsiveness, and resultant tissue damage, and involving the host's cellular humoral, and inflammatory immune response mechanisms. 3) Sufficient information is available from studies of animal models to justify a systematic application of these findings to autoimmune and neoplastic diseases in man. These applications will be in three areas: 1) Characterization of antigens and auto-antibodies in SLE; 2) The role of genetic controls of the immune response in autoimmune disease; 3) Studies of immunocompetent cell populations in diagnosis and treatment of autoimmune and neoplastic disease. The following studies will be done: 1) Application of a computerized information handling system for storage, retrieval, and analysis of clinical, laboratory, and research data; 2) Use of this system to correlate antibodies to DNA and extractable nuclear antigens (ENA) with diagnosis, prognosis, and response to therapy; 3) Physical characterization of the DNA found in the serum of patients with SLE by buoyant density ultracentrifugation; 4) A search for histocompatibility-linked specific immune response genes in man; 5) A search for direct correlations between histocompatibility type, immune response, and disease in autoimmune thyroiditis and in SLE; 6) Characterization of the numbers and functional state of "T" and "B" lymphocytes in patients with SLE, CLL, ALL, Hodgkin's disease, rheumatoid arthritis, and in immunosuppressed patients. BIBLIOGRAPHIC REFERENCES: calin, A., Fries, JF. An "experimental" epidemic of Reiter's Syndrome revisited - follow-up evidence on genetic and environmental factors. Annals of Int. Met. 84:564, 1976. Fries, J. F. A data bank for the clinician. Editorial. NEJM, 1976.